Electric switch



C. C. STIRLING.

ELECTRIC SWITCH.

APPLICATION FILED JAN. 5, 1921.

1 4215550 mm mm, m2

awvamkoz CLAEEQICE G.

STIRLING, OF HARTFORD. CONNECTICUT.

ELECTRIC SWITCH.

Application filed January 5, 1921.

To all Q0710??? it may concern:

Be it known that CLARENCE C. STIRLING, a citizen of the United States. residing at Hartford, in the county of Hartford and State of Connecticut has invented certain new and useful Improvements in Electric Switches, 01 which the following is a specification.

This invention relates to electric switches and more especially to a button or knob therefor by which the switch mechanism may be properly operated but which is effectually prevented from being wrongfully turned off th spindle or equivalent part oi the switch. It is quite commonln certain types of electric switches especlally those involving a rotary spindle as found in the snapswitch kind to have the operating handle or button turned off. This is generally done by young persons and when the button or handle becomes lost the switch cannot be operated.- its will be inferred, I provide means of a positive and certain character by which the button Wlll be properly held to the spindle but the normal action of which will be in nowise 1nterfered with.

In the drawings accompanying and forming part of the present specification. l have shown in detail one or the several forms of embodiment of the invention which to enable those skilled in the art to practice the same will be set forth fully in the following description. I am not restricted to this disclosure. 1 may depart therefrom 111 several respects within the scope of the in vention defined by the claims following said description.

Referring to said drawings:

Figure '1 is a side elevation or a rotary snap-switch furnished with a button or handle involving the invention.

Fig. 2 is a top plan view of the switch.

Fig. 3 is a cross section on the line 3-3 of Fig. 2.

Fig. at is a bottom plan view of the handle or button.

Like characters refer to like parts throughout the several views.

There are a large number of rotary snapswitches of various constructions with which my button or knob may be advantageously employed. 1 have shown in the drawings one of these and sufficient of its construction and action will. be set forth to make clear the nature of the improve Specification of Letters Patent.

the spindle 3 July l, M922.

Serial No. 435,082.

ment. The switch comprises a base as 2 usuallyof porcelain or of some other in sulating material. From the base extends which after the usual fashion is rotary.

Associated with the spindle switch mechanism as at co-operative with contacts as 5. By turning the spindle in the usual manner, the terminals or the switch mechanism 4C will be caused to engage the con tacts to secure the on relation or to break connection therebetween to obtain the off relation. The base 2 suppor's the casing 6 ordinarily of sheet metal and which encloses the switching mechanism and the co-operating contacts. The spindle3 has rigid therewith the lIlClGX plate 7 bearing upon it the symbols on and off which can le read through a slot 8 in the top of the casing 6.

Associated with the spindle is a knob or button as 9, the body 01. which is usually of some insulating material such as vulcanized rubber. It should be explained that the upper end portion of the spindle 3 extends through a central opening in the top oithe casing 6 as quite common in switches of this type. The knob or button 9 has through it as shown the bore or passage 10 which as shown is of two diameters there being as a consequence an annular shoulder 11 which presents a convenient stop for the head or the screw 12 which as shown is hollow and which for reasons that will hereinarter be made plain is capable of turning movement in the knob or button 9. The screw has a hollow internally threaded body 13. the threads of whiclrfit threads on the spindle 3. The lower end or" the body or shank 13 of the screw extends as shown a short distance below the lower face of the knob or button 9 and as represented projects centrally through the washer, plate or disk 14 fittedas represented in a counterbore in the under side of the knob or button and held fixedly in place in some convenient way as by the screws 15.

As shown the shank or body 13 of the screw is surrounded by the coiled spring 16, the lower end of which'has a fixed connec tion with the washer or plate 14 for instance by projecting the lower coil of the spring through a perforation in the washer. The other end of the spring is free although this other or upper end acts against the head of the screw 12. The upper end bears as shown directly against the washer which is fitted against the head of the screw so that the spring cannot become fouled with the head of the screw. This would occur if the slot in the head extended entirely through it.

In assembling the parts the screw 12 is connected by hand with the spindle 3. In Fig. 3 and in Fig. 1 for that matter, the parts are shown assembled. It will be assumed that the knob or button 9 is turned in the proper direction which is to the right in the present case. In this event the spring 16 becomes tightened so that the spindle '3 will be rotated to snap the switch from one of its relations to another. Upon backward motion of the knob or button ,as-would be followed for instance in an attempt tonnscrew it, the button merely turns on the screw 12 acting as a pivot, and before the knob can be separated from the spindle, it is necessary to disconnect the screw 12 from the spindle which is accomplished through the aid of a proper tool by the backward turning of the screw.

It is proper to note that the spring 16 serves two purposes, one as an automatic locking means and the other to hold the button or knob 9 yieldingly to the housing or casing 6. No tools are necessary to apply the knob or button 9 because it can be mounted merely by hand. It cannot, however, be taken off by hand for the reason that the shank'or body 13-of the spindle or screw 12 has been tightened on the spindle by reason of the torque required to snap the switch. There is, however, no grip of this spring 16 on the screw 12 when the button is turned backward in that when the backward motion occurs the spring is enlarged and turns on the screw or spindle 12 without accomplishing anything. On the turning of the button or spindle toward the ri ht, however, the spring is tightened, thus efhecting the proper relation of the spindle of the switch. A proper tool such as a screw driver is required to remove the knob or button.

What I claim is: I

1. An electric snap-switch button, an internally-threaded screw rotative in the 'button, to fitthe external threads of the spindle of the switch, and a spring coiled around the screw, one end of the spring being fixed with respect to the button and the other end being free of the button whereby the spring will be closed when the screw is turned in onedirection and opened when turned in the opposite direction.

2. An electric snap-switch button provided with means for its detachable'connection with the spindle of such a switch, and a coiled spring in the button, the button having means to close the spring when the button is turned in one direction and to open it when turned in the other direction, the

button also having means for transferring the effect of the spring to the spindle when the spring is closed.

3. An electric snap-switch button provided with a'member rotative therein threaded to fit the threads of the spindle of the switch, anda spring coiled around the member, one end of the spring being fixed with respect to the button, and the other being free of the button whereby the spring will be closed when the screw is turned in one direction and opened when it is turned in the other direction.

4. An electric snap-switch comprising a button, an internally-threaded screw rotative in the button to fit the external threads of the spindle of the switch, the head of :the screw being situated below the up per surface of the button, and a spring coiled around the screw, one end of the spring being fixed with respect to the button and the other end being free of the button.

'5. An electric snap-switch button, an internally threaded screw rotative in the button, the screw having a slotted. head below the top surface of the button, and the threads being adapted to fit the external threads of the spindle of the switch, and a spring coiled around the screw, one end of the spring being fixed with respect to the button, and the other end being free of the button.

6. An electric snap-switch button, an internally-threaded screw in the button to fit the external threads of the spindle of the switch, a spring coiled around the screw, one end of which is free of the button and a plate secured to the button around the screw to which the other end of the spring is fixed.

7. An electric snap-switch button, an internally-threaded screw rotative in the button to fit the external threads of the spindle of the switch and having aslotted head located below the upper surface of the button, a disk within the button and fastened thereto, and a coiled spring around the screw, the lower end being fixed tothe disk and the upper end thereof being free.

.8. An electric snap-switch button, an internally-threaded screw rotative in the button to fit the external threads of the spindle of the switch and having a slotted head located below the upper surface of the button, a disk within the button and fastened thereto, and .a coiled spring around the screw, the lower end being fixed to the disk and the upper end thereof being-free, and a disk fitted against the under surface of the head and under which the upper end of said spring engages.

In testimony whereof I aflix my signature.

CLARENCE C. STIRLING.

Witnesses:

.ELSIE M. RABnNsrnIN, HEATH SUTHERLAND. 

